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THE HAND AS AN UNRULY MEMBER. 633 
fact of torsion in the shaft of the humerus I consider as 
fully explaining the above-mentioned peculiarities which 
distinguish the upper from the lower member; while (in 
idea) I untwist the humerus by bringing its back to the 
front, I at the same time unravel the gordian knot of 
that problem which has so long existed as a mystery for 
the homologist.” 
But, before accepting this ingenious solution of the 
problem, you may be inclined to ask how it is, that, if the 
humerus is really twisted, anatomists have never observed 
and described the various stages of the operation, instead 
of simply commenting upon the twisted appearance of the 
bone. This very reasonable question is thus answered by 
a French anatomist, Martins, who in 1857, and appar- 
rently unacquainted with the views of Maclise, proposed 
this very same theory of torsion. 
Martins admits as a “metaphysical difficulty,” the fact 
that the humerus never undergoes the actual operation of 
twisting at all, and that in the earlier stages of growth 
not the slightest traces of torsion exist; but asserts, never- 
theless, that “a virtual torsion does take place during 
growth, and that this produces the same effects as if it 
were real.” The chief indication of this is the raised 
line for the attachment of muscles, which runs obliquely 
upward, from the outer side of the lower end of the hu- 
merus, and is lost upon the posterior surface, giving to 
the lower part of the bone the appearance of having been 
twisted. But it may be seen that the posterior surface 
of the thigh bone presents a similar raised line,even more 
strongly marked, so that there is quite as much reason for 
untwisting that bone, which would leave matters rela- 
tively just as unconformable as at first; and it is well 
known that both these lines are solely for the attachment 
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AMERICAN NAT., VOL. I. 
